广西园林菟丝子发生危害情况调查与分析

【目的】明确广西园林植物种类及菟丝子寄主、种类和分布,掌握其发生危害规律,为园林菟丝子防控提供科学依据。【方法】2011-2013年,每年4-10月,以南宁市为中心选择16个有代表性市（县）进行园林树木及地被植物感染菟丝子实地调查,记录不同树木感染菟丝子种类、生育期、危害的植物学特征及程度,计算感染率和危害指数。【结果】调查鉴定广西园林树木88种,其中菟丝子寄主62种,发生率达70.45%,62种寄主分属39科,51属,其中桑科最多有6种,其次是豆科、大戟科各5种。广西分布有3种菟丝子,分别为日本菟丝子、中国菟丝子和大花菟丝子,还有一种无根藤,它们分别分布在16、9、7和5个市（县）,寄主分别达到38、20、15、11种,分别占寄主的61.29%、32.25%、24.19%和17.74%。南宁市和防城港市菟丝子种类分布最多,3种菟丝子和无根藤均有感染。中国菟丝子主要以种子繁殖危害,每年3月下旬开始萌芽侵染为害,日本菟丝子、大花菟丝子及无根藤主要以藤茎繁殖危害,4月初开始生长,11月果实成熟。寄主危害指数较高的园林树木依次是八月桂、福建茶、龙船花、黄素梅、小叶榕、非洲茉莉,危害指数达4.01-5.48,属于易感树木。【结论】调查鉴定广西园林树木88种,其中菟丝子及无根藤寄主共62种,分属39科,51属;广西分布有3种菟丝子,分别为日本菟丝子、中国菟丝子、大花菟丝子,还有一种无根藤,其中日本菟丝子为优势种类,为重点防控对象。每年4-10月是菟丝子及无根藤主要侵染危害期,也是防除的重点时期。     

泡桐丛枝病类菌原体(MLO)病原传染长春花研究初报

菟丝子(Cuscuta spp.)是一种寄生植物,利用菟丝子为介体可以将植物病毒或类菌原体(mycoplasma like organism)从一株植物传染到另一株植物上。杨一朗陈景耀分别用大豆菟丝子和南方菟丝子为媒介成功地将甘薯丛枝病从甘薯传到长春花上,产生花器叶化、侧枝丛生病状。     

菟丝子寄生后紫茎泽兰的叶绿素及酶类活性变化研究

为寻找防治紫茎泽兰的新方法,利用菟丝子对紫茎泽兰的寄生作用,对寄生后紫茎泽兰的叶绿素、POD、SOD和PAL酶的OD值及其MDA含量的变化进行了测定,结果表明:紫茎泽兰被菟丝子寄生后其叶绿素含量下降,POD和SOD酶活性下降,PAL酶活性则上升,菟丝子防控紫茎泽兰具有一定的可行性.     

Are herbicide‐resistant crops the answer to controlling Cuscuta?

BACKGROUND: Herbicide‐resistant crop technology could provide new management strategies for the control of parasitic plants. Three herbicide‐resistant oilseed rape (Brassica napus L.) genotypes were used to examine the response of attached Cuscuta campestris Yuncker to glyphosate, imazamox and glufosinate. Cuscata campestris was allowed to establish on all oilseed rape genotypes before herbicides were applied. RESULTS: Unattached seedlings of C. campestris, C. subinclusa Durand & Hilg. and C. gronovii Willd. were resistant to imazamox and glyphosate and sensitive to glufosinate, indicating that resistance initially discovered in C. campestris is universal to all Cuscuta species. Glufosinate applied to C. campestris attached to glufosinate‐resistant oilseed rape had little impact on the parasite, while imazamox completely inhibited C. campestris growth on the imidazolinone‐resistant host. The growth of C. campestris on glyphosate‐resistant host was initially inhibited by glyphosate, but the parasite recovered and resumed growth within 3–4 weeks. CONCLUSION: The ability of C. campestris to recover was related to the quality of interaction between the host and parasite and to the resistance mechanism of the host. The parasite was less likely to recover when it had low compatibility with the host, indicating that parasite‐resistant crops coupled with herbicide resistance could be highly effective in controlling Cuscuta. Published 2009 by John Wiley & Sons, Ltd.     

Ion flux kinetics in blue light‐grown field dodder (Cuscuta campestris) seedlings

Previous studies have revealed that blue light stimulates coiling and prehaustoria development in young de‐etiolated dodder seedlings prior to host attachment. In this study, the Ca²⁺ and H⁺ flux kinetics that are associated with blue light‐mediated coiling and prehaustoria development in de‐etiolated dodder seedlings were measured uninvasively using the ion‐selective, vibrating microelectrode ion flux system. The findings showed that blue light induces rapid transient changes in the net Ca²⁺ and H⁺ fluxes. A clearly pronounced lag of about several minutes was observed between the blue light‐induced changes in the Ca²⁺ and H⁺ fluxes, with H⁺ being a leading ion. The addition of 1 mol L^?1 vanadate, a known blocker of the plasma‐membrane H⁺‐ATPase, to the bathing solution completely prevented both the H⁺ and the Ca²⁺ flux responses and inhibited coiling and prehaustoria development, suggesting a causal relationship between the blue light‐induced changes in the net Ca²⁺ and H⁺ fluxes and seedling movements. It is concluded that the plasma‐membrane H⁺‐ATPase plays a key role in a dodder's parasitic mode of growth and its adaptive response to the environment.     

园林菟丝子生防真菌的筛选研究

首次从大花菟丝子感病藤茎上分离到半裸镰孢、腐皮镰孢、细交链孢和茶褐斑拟盘多毛孢等４种病原真菌。室内致病性试验结果表明这４种真菌均能使日本菟丝子和大花菟丝子感病而死,致病力由强到弱的顺序是：腐皮镰孢、半裸镰孢、茶褐斑拟盘多毛孢和细交链孢。     

Blue light induced changes in inositol 1,4,5-trisphosphate in Cuscuta campestris seedlings

Previous studies revealed that blue light stimulates and red light inhibits prehaustoria development in young seedlings of the parasitic weed Cuscuta campestris (field dodder). This study showed a positive correlation between blue light induced increases in inositol 1,4,5-trisphosphate (IP₃) and blue light-mediation of prehaustoria development, prior to host attachment. Blue light induced a significant increase in the level of IP₃, with a peak at about 30 min. Thereafter, the level of IP₃ declined to the resting value after 2 h of blue light. Irradiation with 10 min red light pulse applied directly at the end of each 0.05, 0.1, 0.15, 0.2, 0.3, 1, 2 and 4 h blue light significantly reduced IP₃, while high levels of IP₃ were observed after 10 min far-red pulse. The G-protein inhibitor pertussis toxin inhibited prehaustoria developed under blue light, suggesting that receptor-coupled G-proteins are likely to be involved in prehaustoria development. These results are the first in vivo demonstration of a possible role for IP₃ as a second messenger in the blue light signal transduction process in prehaustoria development in Cuscuta .     

新疆苜蓿菟丝子综合治理技术体系

菟丝子是苜蓿田中最常见的一年生寄生性恶性杂草,是世界性的杂草检疫对象.近年来由于对引种苜蓿种子的检疫检验重视不够,以及苜蓿地田间管理粗放等原因,菟丝子的传播范围越来越广,对草业生产造成的危害也日趋严重.在对苜蓿菟丝子进行了多年调查研究的基础上,阐述了菟丝子的生物学特性、危害特点和发生规律等.并系统的提出了植物检疫、农业防治、物理防治、化学防治和生物防治等较为有效的菟丝子综合治理技术体系.     

不同炮制方法对菟丝子中多糖含量的影响

目的考察不同炮制方法对菟丝子中多糖含量的影响。方法采用硫酸-苯酚比色法测定菟丝子不同炮制品的多糖含量。结果菟丝子不同炮制品多糖含量有差异,生菟丝子多糖含量为5.34%,经酒炙后是其生品的1.98倍,是清炒品的1.62倍。结论菟丝子经炮制后能显著提高多糖的含量。 更多还原